Eccentric driven high pressure pump



Aug. 8, 1933. w. E. GOLDSBORO UGH 1,921,816

ECCENTRIC DRIVEN HIGH PRESSURE PUMP Filed May 51, 1929 3 Sheeii$-Sheet 1Snow/hm a. GoLDsBoRoueH Aug. 8, 1933. w. E, GOLDSBOROUGH 5 I ECCENTRICDRIVEN HIGH PRESSURE PUMP Y Filed May 31, 1929 s Sheets-sheaf 2 hvambozWlNDER E. eowssonoucm 331 hi elf/01m;

Aug. 8, 1933. w. E. GOLDSBOROUGH 1,921,816 7 ECCENTRIC DRIVEN HIGHPRESSURE PUMP Filed May 31, 1929 -s Sheets-Sheet s gvwemtoz @51 1115 a ttome Patented Aug. 8, 1933 UNITED STATES PATENT OFFICE ECCENTRIC DRIVENHIGH PRESSURE PUMP Winder E. Goldsbcrough, South Norwalk, Conn, assignorto Doherty Research Company, New York, N. 51., a Corporation of DelawareApplication May 31, 1929. Serial No. 367,242

5 Claims. (ill. lug-4:2

This invention relates to pumps, more particularly to pumps designed toforce liquid under high pressures through a fine orifice or nozzle forthe purpose of atomizing the same.

It is among the objects of this invention to provide a pump which shallbe of simple, compact and rugged construction, durable and efficient inoperation, and capable of supplying liquid at high pressures withouttransmitting severe shocks to the actuating mechanism.

In many industrial processes, it is desirable to highly atomize a liquidfor the purpose of altering it either chemically or physically, or forthe purpose of ,obtaining a high degree of comminution or atomization.It. is also desirable in connection with many such processes toaccurately measure the quantity of liquidatomized with each repetitionof the process or cycle. For example, in engines of the type commonlyknown as solid injection engines, it is the practice to supply fuel tothe working cylinder when the piston thereof is at or near its upperdead center position. In order to obtain proper atomization of the fuelwithout the aid .of compressed atomizing air it is desired that thepressure of the fuel be as high as practicable, pressures of from 2000to 16,000 pounds per square inch having been tried. The quantity of fuelis varied in accordance with the load, or the will of the operator, andthe timing of the injection is varied in a manner analogous to thevariation of the spark in an Otto cycle engine. In such enginesthecontrol of the quantity of fuel supplied and also the timing of theinjection present difficult, vital problems because the quantity of fuelcomprising the fuel charge for any one cycle is small and a variation ofbut a few drops in the case of a large engine or the fraction of a dropin the case of a small engine seriously affects the efficiency. The sameconditions are met with in certain types of combustion turbines and inother relations.

It is one of the objects of this invention to provide a pump capable ofaccurately measuring oil or other liquid under varying conditions andsupplying the same under the desired pressure to the point at which itis to be atomized in properly timed relation to the cyclic occurrencesin the process in connection with which it is used.

It is a further object of this invention to avoid working against highpressure when varying the quantity of fluid supplied by the pump or thetiming of its discharge. To this end, it is a feature of this inventionthat both of these variations are effected by means of a singlecylindrical member surrounding a pump plunger, the move ments of whichare not affected by the pressure in the pump chamber. Longitudinalmovement of the cylindrical member is preferably used to vary thetiming, while rotation of the cylindrical member about the plunger ispreferably used to vary the quantity.

In the engine of the type referred to, it has heretofore been impossibleto change from the grade of fuel for which the pump was designed toanother grade of entirely different calorific value. It thus occurs whenthe preferred fuel is unavailable, or another grade becomes moreplentiful, that the old pump designed to function upon the old fuel isnot suitable because the quantity of the two fuels required for the samepower output is greatly different and beyond the ordinary range ofquantity adjustment ordinarily provided.

It is one of the objects of this invention to provide a construction inwhich a major adjustment in capacity can be made other than thatprovided for variations in load. To this end, it is one of the featuresof this invention to provide a plurality of interchangeable pump barrelsand c0- acting plungers so that great changes in capacity of the pumpmay be made with little delay.

These and other objects of the invention will be more particularlydescribed in connection with the accompanying drawings, in which:

Fig. 1 is a longitudinal section through one form of pump constructed inaccordance with this invention, parts being sho .l in side elevation;

Fig. 2 is a section taken on the line 2-2 of Fig. 1, parts being shownin side elevation;

Fig. 3 is a section taken on the line 33 of Fig. 1, parts being shown inside elevation;

Fig. 4 is a top plan view'showing the construction of the groove in thecontrol member;

Fig. 5 is a longitudinal section through a pump illustrating a modifiedform of construction;

Fig. 6 is a section taken on the line 6-6 of Fig. 5;

Fig. 7 is a diagrammatic view illustrating the construction of thecontrol member used in connection with the pump shown in Fig. 5; andshowing the same as it would appear if opened and rolled out flat. v

Fig. 8 illustrates the use of interchangeable plungers and liners forthe purpose of altering the capacity of the pump.

Referring particularly to Fig. 1, 10 designates a housing forming themain body of the pump and having a bore 12 of varying diameter extendingtherethrough. A pump barrel or liner 14 is inserted in one end of thebore 12 and is held against a shoulder 16, formed by an enlargement ofsaid bore, by means of the bushing 18.

A double-acting piston 20 formed of a rod 22 and an enlarged portion 26integral with said rod is reciprocative in bore 12. The enlarged portion26 is shouldered at 28 and forms with the housing 10 an annular chamber30 between the shoulder 28 and a shoulder 32 formed in the hous-.

ing 10 by an enlargement of the bore 12. The enlarged portion 26 has alarge bore 84 extending partially therethrough and connecting with asmaller bore 36. A plunger 38 is removably inserted in the large bore 34and is adapted to slide with a close fit in the pump barrel 14 uponreciprocation of the rod 22. The plunger member 38 has a bore 40extending longitudinally therethrough and which is adapted to form witha rod 42 an annular channel forming a free passage for the flow of fuelthrough the plunger. The rod 42 is provided with an external screwthread at one end adapted to screw into the internal screw thread ofbushing 44 to retain the plunger member 38 in the large bore 34.

The member 20 is provided with a bore 46 extending diametricallytherethrough and adapted to contain a housing 46 of a valve-56. Anexternally threaded bushing 52 retains the valve housing 48 upon ashoulder 54 formed by an enlarged portion of the bore 46. The valve 50is provided with a seat 55 adapted to coact with a seat 56 in' aremovable bushing 58 in the opposite end of the bore 46. A stem 60 ofthe valve 56 extends through the bushing 58 and projects through thepiston 20 to slide upon the cylindrical wall of the pump. This portionof the pump wall in this instance is formed by a semi-cylindricalcontrol member 62 having a groove 66 extending along the surface thereofas may be more particularly seen in connection with Fig. 4.

In order to regulate the quantity of fuel supplied to the engine andalso the timing of the injection into the engine, an adjusting member 64is provided surrounding the rod 22 and closing one end of the bore 12which forms the pump cylinder. The member v6-4 is adapted to be roatedabout the rod 22 to shift the member 62 ubntaining the groove 66angularly about the piston 20. The mechanism for effecting thisadjustment may be more particularly seen in Fig. 2 in which a splitbushing 68- is rigidly connected by meansof a screwbolt 70 with a shortsleeve '72 surrounding the adjusting member 64. The

short sleeve .72 is slidable relative to the adjust-' ing member 64 butangular movements of the same are transmitted to the adjustment memberby means of a key 74. The split bushing 68 is provided with an arm orextension '76 adapted to be connected by means of a ball and socketjoint indicated at 78 to a rod 80 which may be manually or governorcontrolled as desired.

80 are transmitted by the mechanism just described into the angularmovements of the control member 64. Such movements of the control memberrotate the semi-cylindrical member 62 relative to the piston 20,bringing a wider or a narrower portion of the groove 66 depicted in Fig.4 adjacent the end of the valve stem 60 of the valve 50. Referringparticularly to Fig. 4 it will be seen that the groove 66 in thesemicylindrical member 62 is formed with one of its edges 82 forming astraight line lying in a single transverse plane taken through the axisof the pump plunger. The opposite edge 84 of the groove 66 is curvedaway from the edge 62 forming a continually widening depression.

The semi-cylindrical member 62 is preferably formed separately from itsadjusting member or sleeve 64, and removably connected thereto by ascrew bolt 63. It may readily be seen however that the member 62 mightbe an integral part of sleeve 64.

Liquid is supplied to a suction chamber 86 formed in the rear end of thepump by means of a supply line 88 which line leads to any convenientsource of supply which may be under any desired head, or whereconditions permit may even be below the pump and drawn up thereto bysuction in the suction chamber 86 In the operation of the device thusfar de scribed, liquid isdrawn into the suction chamber 86, under anydesired pressure head upon movement of the piston 20 to the right bymeans oi eccentric 92. Upon the return movement of the piston 20 to theleft, the liquid in the suction chamber 86 is forced by the pistonthrough the space 94 between the grooved member 62 and the said piston,thence through valve 50, the passage 36, the annular channel surroundingrod 42 in the removable plunger member .38 to the pressure chamber 98.The displacement of the enlarged portion 26 of the piston 20 beinggreater than the displacement of the removable plunger member 38, fuelis displaced during the movement 'of the plunger to the left faster thancan be accommodated in the pressure chamber 98. In order to accommodatethis difierence, an additional chamber is provided which is formedbetween the inner edge of the pump barrel 14 and the shouldered portion102 of plunger 38. The displacement in chamber 100 together withdisplacement in the pressure chamber 98 are made exactly equal to thedisplacement of the enlarged. portion 26 of piston 20 in the suctionchamber 86, so that upon movement of piston 20 to the left, the decreasein the volume of suction chamber 86 is exactly equal to the increase involume in the two chambers 98 and 100. Suction chamber 86 is' connectedwith chamber 100 by means of continually open passages 104 and 106,provided in the housing member 10, so that upon movement of the plungerto the left fuel or other liquid is displaced from chamber 86 into bothchambers 98 and 100, without any material increase in pressure insuction chamber 86, or a decided decrease in pressure in chamber 98 orchamber 100. 7

Assuming that the piston 20 has been moved as far as possible to theleft by eccentric 92, further rotation of the eccentric moves the pistonto the right. During the early portion of this movement, the stem 60 ofthe valve 50 rests upon the plane surface 67 of the grooved member 62,retaining said valve in open position so that the pressure chamber 98 isin open communication with the suction chamber 86. Therefore the fueldisplaced in chamber 98 passes to chamber 86 without a material increasein pressure. At about the mid-stroke of the piston .20, that is, whilethe same is being driven at its highest velocity.by means of theeccentric 92, the stem 60 of the valve 50 slides over the edge 82 ofgroove 66, so that the valve 50 is closed. Pressure in the chamber 98 atonce builds up to a high value overcoming the resistance of the nozzleso that a charge of liquid is injected into the combustion chamber orother device to which the nozzle is connected. During the interval inwhich the valve 50 is closed and liquid is being displaced from thechamber 98 through a nozzle 108, fuel is drawn into the chamber 86 fromthe main supply. This interval is very brief relative to the entirestroke of'the piston 20, since the stem 60 of the valve 50 soon contactswith the opposite edge 84 of the groove 66, and is opened thereby. Thepressure in chamber 98 is at once released, and further displacement ofthe plunger in this chamber merely forces fuel through the pistonpassages and past the valve 50 into the chamber 86. The pressure inchamber 98 is thus abruptly reduced permitting a sharp termination ofthe injection into the engine cylinder or other mechanism wherebydripping at the nozzle is prevented and all the liquid is eflicientlyatomized. Upon movement of the piston 20 to the left, the valve 50 isheld open both positively by reason of the fact that the stem 60 of thevalve rests upon the surface 6'7 and also because of the flow of liquidduring this period from the chamber 86 to the chamber 98. Thus when thevalve stem 60 crosses the groove 66 upon movement of the piston 20 inthis direction, the valve does not close as it does when traversing thegroove in the opposite direction, due to'the pressure of the fuelthereon, so that. a negative pressure is at no time created in thechamber 98 during the operation of the pump.

Changes in the timing of the pump relative to its driving mechanism areeffected by longitudinal movements of the grooved member 62 relative tothe piston 20. The elements for efiecting this variation consist of acollar 110 flexibly connected by means of pins 112 or equivalentelements, with an annular groove 114 in the control member 64, so thatmember 64 is free to rotate relative to collar 110, the longitudinalmovements of the one being transmitted to the other. The collar 110 hasan internally screw threaded portion 116 which is adapted to coact withan externally screw threaded portion 118 upon a sleeve or bushing 120which is keyed to the rod 22 of the pump by key 122 in a mannerpreventing angular movements of said bushing relative to the rod whilepermitting relative longitudinal movements thereof. The bushing 120 isrigidly fixed by means of projection 124 to the frame 126 of the engine.By rotating collar 110 about the bushing 120 the collar is screwed tothe right or to the left, and its longitudinal movement transmittedthrough the pins 112 to the control member 64, which in turn draws orpushes the grooved member 62 to the right or left. Thus the stem 60 ofthe valve 50 traverses the groove 66 earlier or later in the stroke ofthe piston. Since the eccentric shaft 128 is driven by and in unisonwith the main shaft of the engine or other machine, the point in itscycle at which the valve 50 traverses the groove 66 is thereby alteredto alter the time of injection. A lock nut 130'is provided adjacent thecollar 110 to insure that the timing mechanism will not be altered dueto the operation of the pump.

Fig. 5 illustrates the invention in a slightly modified form. In thisconstruction all the parts are similar and analogous to those shown inFig. 1 except that instead of the grooved member 62 coacting with avalve carried by the piston, a-

collar 132 is provided with openings 134 and 136, which leave a strip ofmetal 138 therebetween. The formation of this strip closely correspondsto the conformation of the groove shown in the grooved member 62. Theplunger is provided with. a pair of valveless passages 140 extendingdiametrically therethroughi It will be seen that when these passages areadjacent the openings 134 and 136, the supply chamber 142 will be inopen conmiunication with the pressure chamber (not shown) in a manneranalogous to the communication between chambers 86 and 98, in thepreviously described construction when valve 50 is raised above thesurface of seat 56. When the passages 140 are adjacent the metal strips138 the passage is closed thereby the same as passage 46 is closed byvalve 50 when the valve is traversing the groove 66. In other respectsthe operation of this construction is identical with that of the formpreviously described.

It will be seen that thefirst described construction is more to bedesired when the pressures to be attained are extremely high, that isapproaching the limit of those mentioned, while the last describedconstruction is suitable in case the pressures required are, while high,not so extreme as to cause leakage.

It will be seen that both constructions described provide a pump inwhich both the quantity of liquid supplied and the timing of such supplymay be separately and individually altered by movements of a singlemember.

It will be understood that while there has been hereindescribedconstructions in which the control member is moved angularly orlongitudinally of the plunger to eifect the desired variations, anymovement of one of these members relative to the other may be used toeifect the same end. That is, the piston 20 might be ro- .tated whilethe control member remains staor liquids of widely varying composition.The

,plunger being actuated preferably by an eccentric, provides a simpleharmonious motion of the reciprocating parts while the point ofinjection at all times corresponds fairly closely to the maximum speedof the plunger, whereby high pressures are rapidly attained at theinstant desired, yet without severe shock to the actuating mechanismbecause the parts are already moving at their highest velocity in thedesired direction, and it is not necessary to overcome both inertia ofthe reciprocating parts and the pressure of the liquid at the same time.

While but two forms of construction of fuel pumps in accordance withthis invention have been described, it will be apparent to those skilledin the art that many alterations and modifications of the members hereindisclosed are practicable.

While the invention is particularly useful in connection with internalcombustion engines and combustion turbines it will be readilyappreciated that the same is useful in many other positions.

Having thus described the invention what is claimed as new is:

1. In a pump, a cylinder, 9. plunger reciprocative therein, a sleevesurrounding said plunger having a groove in the surface thereof, apassage in the wall of the plunger adapted to cross said groove in thecourse ofthe reciprocation of said plunger, means whereby only thatportion of the plunger stroke during which said passage traverses saidgroove is effective in forcing fluid from said pump, and means wherebythe width of the groove traversed by said passage is varied to vary thequantity of fluid forced from said cylinder upon each stroke of saidplunger.

2. A pump for supplying fuel having a suction chamber and a pressurechamber, a plunger reciprocative in said pressure chamber, means todisplace fuel from said suction chamber to said pressure chamber duringthe suction stroke of said plunger at a rate which is at all times equalto the rate of evacuation of said plunger.

3. A pump for supplying fuel from a source of supply, including acylinder forming at one end a supply chamber in open communication withsaid source of supply, and at its opposite end a pressure chamber, apiston reciprocative in'said cylinder, passaged means extending from oneend of said cylinder to the other whereby fuel passes from the supplychamber of said cylinder into said pressure chamber during the outwardmovement of said piston at a rate which is at all times equal to theevacuation of the piston in said pressure chamber.

4. A fuel pump having a housing, a pump barrel removably inserted insaid housing, a piston rod extending through said housing and connectedwith a plunger reciprocative therein, a supply chamber on the piston rodside of said plunger, a plurality of chambers on the opposite side ofsaid plunger communicable therewith, the effective area of the plungeron the piston rod side of said plunger being equal to the sum of theeifective areas upon the opposite side of said plunger.

5. A pump having a cylinder, a passaged plunger reciprocative in saidcylinder, a valve extending diametrically through said plunger, andpositive means to actuate said valve in the course of the reciprocationof said plunger.

6. A pump having a cylinder, a passaged plunger reciprocative in saidcylinder, a valve extending diametrically through said plunger andpositive means to actuate said valve at a variable point in the courseof the reciprocation of the plunger.

WINDER E. GOLDSE-OROUGH.

